1. Field of the Invention
The present invention relates to an air conditioning system with a compressor that changes the flow rate of a refrigerant to be discharged, furthermore, the invention is applicable to an air conditioning system in which the compressor for the air conditioning system is driven by an electric motor.
2. Description of the Related Art
Conventional vehicle air conditioning systems have an intermittent operation mode in which the compressor is operated intermittently for the required operating time. While after-evaporator temperature is lower than or equal to wet-bulb temperature, intermittent operation mode is exercised after a lapse of a certain elapsed time since the compressor (engine) stops. On the other hand, when the after-evaporator temperature is higher than the wet-bulb temperature, the intermittent operation mode is stopped to prevent odor components that adhere to the surface of the evaporator from being scattered into the cabin (for example, see Japanese Patent Laid-Open Publication No. 2002-248933.
The invention described in Japanese Patent Laid-Open Publication No. 2002-248933 has the following problem if it is applied to an air conditioning system with a compressor, such as an electric compressor, that continuously controls the discharge flow rate of the refrigerant down to zero.
That is, in the invention described in Japanese Patent Laid-Open Publication No. 2002-248933, intermittent operation mode is exercised based on the instant when the compressor (engine) stops. Thus, even after the discharge flow rate of the refrigerant becomes approximately zero, intermittent operation mode will not be exercised while the compressor is in operation.
Consequently, even though many of the odor components adhering to the surface of the evaporator are being scattered into the cabin, intermittent operation mode will not be exercised. This causes the problem that many of the odor components adhering to the surface of the evaporator are blown into the cabin.